System and methods for countering satellite-navigated munitions

ABSTRACT

A defense system that receives information regarding an incoming object(s), then automatically coordinates spoofing or jamming of SATNAV signals potentially used by the incoming object(s) while also informing friendly systems of the spoofing or jamming of SATNAV signals.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a non-provisional application claiming the benefitof U.S. Provisional Application Serial No. 61/786,066 filed Mar. 14,2013 entitled “System and Methods for Countering Satellite-NavigatedMunitions,” the entirety of which is hereby incorporated by reference.

TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to disrupting attacks fromincoming projectiles through electronic warfare and electronic countermeasures. More particularly, the invention relates to tracking incomingprojectiles through the use of radar, then jamming or spoofingsatellite-guided or satellite-navigation (SATNAV) frequencies used byincoming projectiles for navigation.

BACKGROUND OF THE INVENTION

Hostile unmanned aerial vehicles and precision guided munitions (PGMs)frequently use satellite signals to navigate to a designated target.Such PGMs can include, for example, guided mortars, guided artilleryprojectiles, unmanned aerial vehicles (UAVs), missiles, glide bombs, andother projectiles capable of acquiring and using global positioningsystems (GPS) or other SATNAV signals for guidance. A typical SATNAV PGMguidance system receives satellite signals to guide itself to adesignated target. The satellite signals can be based on GPS technologyor SATNAV alternatives to GPS, such as GLONASS, Galileo, or Beidou forexample.

Current countermeasures against incoming objects use projectiles, suchas bullets, that are configured to destroy or to disrupt the trajectoryof an incoming projectile. The problems with countering a projectilewith a counter-projectile, however, are numerous including thepossibility of inadvertently striking a friendly aircraft or civilianbuildings, reloading issues, shrapnel, and the possibility of misfiring.

Another countermeasure option involves the use of a targetedelectromagnetic beam to heat a projectile to a disruption temperature todeflagrate the projectile. This solution, however, also risks potentialproblems with inadvertently damaging civilian aircraft or infrastructureand issues involving the energy or chemicals such a system wouldrequire.

Another countermeasure option, for missiles or weapons targetingvehicles in motion, is described in U.S. Pat. No. 7,489,264. That optioncontemplates using multiple electronic signals to coordinate electronicjamming signals for protecting multiple vehicles physically separatedfrom one another against Home-on-Jam weapons. The vehicles exchangemessages and coordinate a system to emit an alternate jamming signalcreating a false target. The '264 system, however, does not contemplatea satellite guided projectile or a fixed-position defense.

Another countermeasure option, for SATNAV broadly, is to disrupt oreliminate satellite communication for all area-wide guidance systems atthe satellite's transmission. This elimination, jamming, or spoofing ofall satellite communication, however, would also disrupt all nearbyequipment that also relies on SATNAV signals to operate, including UAVs,communication systems, and hand-held GPS navigation devices. Theconsequences of persistently jamming or spoofing all SATNAV signals inorder to disrupt an incoming PGM attack would severely disrupt broadmilitary and civilian activities. Additionally, there might be seriousdiplomatic consequences for disrupting the SATNAV signals of a systembelonging to another state or, for example, on an expeditionary forcedisrupting the use of civilian GPS signals in a foreign city.

Hence, it is known to coordinate the transmission of jamming signalsfrom a plurality of cooperating vehicles, and to shut down all STANAVguidance systems through disruption of satellite transmissions. However,there is yet no technical solution for targeted defending of a fixedposition or base against incoming projectile(s) through disruption oflocalized satellite signals guiding the projectile(s).

SUMMARY OF THE INVENTION

The exemplary implementations herein can alleviate the above problem andthus provide an efficient and reliable solution for improving aposition's chances of evading any incoming projectile guided by SATNAVwhile allowing general satellite communications to continue in an area.

According to exemplary implementations, the system can consist of one orseveral directional and omnidirectional SATNAV jamming or spoofingantennae linked to a computer with software capable of processing datasent from detection systems such as battlefield radars. Various systemsof the invention can direct and coordinate the jamming or spoofingactivity of the antenna or antennae based on data provided by otherdetection systems and pre-set user inputs. When an incoming projectileattack is detected, the system can automatically analyze data sent byother systems and can respond based on other inputs to, for example,automatically direct a targeted directional SATNAV jamming beam toilluminate (and in some example implementations to misdirect) on one orseveral projectiles.

In other implementations, by providing a user with pre-set operationalmodes and the ability to customize the activity of the SATNAV jamming orspoofing antenna or antennae, the system's software management canenable front-line personnel to operate the invention or restrict thesystem to no user input. The system can enable automatic directionalSATNAV jamming or spoofing against all potential inbound precisionguided munitions while still allowing the use of friendly SATNAV systemswith no disruption.

In other implementations, the system can automatically activate an audiosignal to reassure personnel that SATNAV PGMs are being jammed to reducethe potential psychological strain of an attack.

In other implementations, to prevent munitions from accurately homing inon jamming antennae, the system can include automatic switches to turnvarious antennae on and off in rapid succession while still maintainingpersistent jamming of the targeted SATNAV signals. This automatic systemcan coordinate several directional antennae tracking a target, ortargets, and emitting identical SATNAV jamming signals to switch on andoff while still ensuring that the targeted object or objects arepersistently illuminated.

Other advantages, advantageous features and applications of theexemplary system and implementations thereto will be apparent from thefollowing description and the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an electronic warfare situation in which theexemplary implementations (i.e., embodiments) can be employed tomisdirect an incoming projectile through the use of SATNAV jamming.

FIG. 2 shows example block diagrams of an example implantation of asystem's operability functions.

FIG. 3 shows an example flow diagram for the system illustrating variousinformation sources and outputs.

DETAILED DESCRIPTION OF THE INVENTION

The following section describes example implementations of a centralizedSATNAV jamming system to protect positions from incoming projectiles.

FIG. 1 illustrates an example battlefield radar, or other detectionsystem, 101 which detects a possible hostile incoming object(s), 102.The aerial object might be an unmanned aerial vehicle (UAV), a mortarround, a missile, a bomb, or some other type of projectile guided bysatellite navigation. The incoming object might be a SATNAV precisionguided munition (PGM). Counter-battery radar systems that detectincoming objects already exist, and are known to those of ordinary skillin the art. Counter-battery radar systems, for example the AN/MPQ-64 orthe AN/TPQ-48, automatically detect incoming attacks and have beenimplemented with systems that automatically generates an alert, forexample sounds an alarm. These systems are often operative to determineand identify the origin, type, and position of the incoming object.After detecting a possible attack, the detection system can beprogrammed to automatically transmit available data concerning thelocation, velocity, and type of incoming projectile to the directionaljamming system 103. The data can be received by example implementationsof the invention. In addition to the battlefield radar data, thedirectional jamming system 103, can receive inputs by a user and/or datafrom a separate targeting radar, 104. The system would then process theinformation and transmit (or emit) a SATNAV jamming signal or signals,105, at the suspected projectile, disrupting any possible SATNAVguidance.

The jamming signal(s), 105, can be a focused directional jam to blockany potential SATNAV signal acquisition by the suspected incomingobject, or can include an omnidirectional jamming signal, which can beused in situations in which there are many incoming objects approachingfrom more azimuths than the system has directional antennas or thejamming signal(s) can be a combination of directional andomnidirectional jamming. The precise automatic response can bedetermined based on pre-set user inputs to the system's operatingsoftware. Additionally, since it can be undeterminable whether theincoming object is a PGM, the jamming signals can be transmitted atsuspected PGMs regardless of confirmation that the projectile issatellite navigated. The system can also transmit or emit a signalwarning nearby systems that a SATNAV jammer is active. This warning canbe embedded in the jamming signal itself to friendly devices usingsatellite navigation.

After the directional jamming system 103 has jammed the signal(s)potentially received by the projectile 102, the projectile can continueunguided or potentially be destroyed by a separate system. The SATNAVguided PGM will be unable to acquire a SATNAV signal, can fly unguided,and can have a greater chance of not striking its intended target.Although aerial objects have been discussed, example implementations ofthe invention can also be used to disable other types of incomingobjects, which can be, for example, a ground-based vehicle, such as anunmanned small rover or car, or water-based incoming objects, includingthose detectable by infrared, optical, or sonar systems, as opposed tobattlefield radar systems. Examples of such water-based incoming objectscan include unmanned submersible craft, unmanned surface vehicles, andtorpedoes.

The directional jamming system 103, can comprise one or more computersystems having one or more microcontrollers, memory devices, storagedevices, and input/output devices. Each of these components can beinterconnected using, for example, a system bus.

The one or multiple microcontrollers, within directional jamming system103 can be one or more processors, or application-specific integratedcircuits and can process instructions for execution within the system.In some implementations, the processor can be a single-threadedprocessor. In other implementations, the processor can be amulti-threaded processor. The one or more microcontrollers can becapable of executing or processing computer instructions stored in oneor more memory devices, or on one or more storage devices. The softwaremodules can be operable to allow the system to receive one or moreinputs, process the inputs, and relay one or more commands or orders.

The one or more memory devices within directional jamming system 103 canstore a variety of information and data, including data received from,for example, counter-battery radars and user inputs. In oneimplementation, such memory can be a computer-readable medium. Thememory devices can include both volatile memory and non-volatile memory,including such devices as RAM, ROM, Flash, PROM, EPROM, EEPROM, etc.

The one or more storage devices within directional jamming system 103can be capable of providing mass storage. The storage device(s) can be acomputer-readable medium, and in various different implementations, caninclude a hard disk device, an optical disk device, flash memory, solidstate drive, or some other storage device.

One or more input/output devices within directional jamming system 103can provide input/output operations. In example implementations, theinput/output device can include one or more public service telephonetrunk interfaces, for example an RJ11 connector, an IP network interfacedevice, for example an Ethernet card, a cellular network interface, forexample LTE, a serial communication device, for example an RS-232 port,and/or a wireless interface device, for example an 802.11 wirelesstransceiver. The input/output device can include driver devicesconfigured to receive input data and send output data to otherinput/output devices, as well as sending communications to and receivingcommunications from various networks.

Example implementations of the directional jamming system 103 can beoperable to process a variety of inputs, based on the level of risk auser of the system is willing to accept, as well as the particularthreats that the user faces. The system 103 can address, for example,how focused the directed jamming signals can be, how quickly andprecisely the jamming signals can be moved to “trace” the targetedmunitions, how powerful the jamming signals should be, and what is thebest compromise between safety and possible civilian/friendly SATNAVdisruption.

With reference to FIG. 2, example implementations can be operable toreceive a variety of data inputs and execute a variety of differentoutputs. In example implementations, the system 103 can have one or moreinterface modules for receiving those inputs. The devices that providedata to the system 103 can also have one or more modules for interfacingwith the invention.

As illustrated in FIG. 2, the system 103 can be operable to receive datainput 201 from a variety of detection systems. For example, the system103 can receive data from one or several counter-battery radar systems,101. The counter-battery radar, via one or more interfaces, can senddata, such as location and trajectory information, concerning anincoming object. The system 103 can be tuned for optimal performancewith a wide variety of battlefield radar systems and other detectionsystems. Advance knowledge of the margins of error and toleranceprovided by different systems can be used to configure how tight or widethe broadcast SATNAV jamming signals, 105, are. In exampleimplementations, the system 103 can be deployed in a configuration inwhich the system 103 possesses its own targeting radar 101. Data from acounter-battery radar system can be used to determine the search areafor the targeting radar resulting in the possibility of a more precisejamming signal.

As shown in the FIG. 2 example flow chart detailing a exampleoperability functions, implementations of the system 103 can functionwith a computer containing decision-making software 204 that receives adigital signal 201 from a variety of detection devices including inputfrom, for example, a counter-battery radar 101. In this example, thebattlefield radar 101 can provide a digital signal 201 to the computercontaining the decision-making software 204 regarding the type,location, speed, and trajectory of an incoming projectile in relation tothe system's 103 location. The system 103 can also receive data fromother outside devices 203 including, for example, an IdentificationFriend/Foe device (IFF), Blue Force Tracker (BFT), or an equivalentidentification system. The data provided by these devices can, forexample, provide the system 103 with information indicating when afriendly aircraft (or a critical item that is dependent on SATNAV) iswithin range of the system's jamming signal. The computer containingdecision-making software 204 can operate according to user inputs 205and can also incorporate data from a battlefield targeting radar(s) 202.After the computer containing decision-making software 204 hasdetermined an action, it can be operative to order jamming antennaemicro-controllers 206 to activate and direct the operation ofdirectional SATNAV jammers 207, omni-directional SATNAV jammers 208, andmechanical actuators 209 which can orient the directional SATNAV jammers207. Additionally, the system 103 can provide output data feedback 210to other devices such as BFF or IFF.

The system 103 can be operable to automatically transmit anomnidirectional signal along pre-set frequencies when an indirect fireattack involving an incoming object, which can be a PGM, is detected.The system 103 can allow a user to specify that omnidirectional SATNAVjamming signals be activated for a specified period. The user candesignate the omnidirectional jamming mode and the specified period, forexample, in a situation in which the incoming object's target (e.g., amilitary base) is remote and there is little fear of omnidirectionaljamming signals impacting the acquisition of SATNAV signals related tonon-hostile operations.

In some example implementations of the system 103, the SATNAV jammingsignals 105 can be automatically directed in the predicted location ofan incoming object 102, or objects, or transmitted more precisely at anincoming object(s). In example implementations, the system 103 can beoperable to receive a user input that specifies the tightness of thedirectional jamming signal 105, and can also be operable to allow thewidth and strength of the jamming signal to be specified by the user. Inexample implementations, the system 103 can be operable to transmitmultiple jamming signal(s) directed at multiple incoming targets frommultiple azimuths using, for example, separate transmitting emitterslike directional antennas. The system 103 can also transmit directionaljamming signals in a single arc that can be spread to cover multipletargets. The system 103 can be operable to transmit the SATNAV jammingsignals 105 to illuminate an object until impact, or to illuminate theobject for a user-specified period, or to only illuminate an object itis traveling through certain altitudes, or certain areas. In exampleimplementations, the system 103 can focus the directional jamming modefunctions sufficiently so as not to disrupt friendly devices that alsouse satellite signals. Thus, the system 103 can be used in areas whereother nearby non-hostile systems depend on SATNAV signals.

In example implementations, the system 103 can also be operable toswitch from a directional jamming mode to an omnidirectional jammingmode or vice versa. Here, for example, the system 103 might begin in adirectional jamming mode. Should attacks from multiple azimuths (or anumber of incoming rounds above a user-specified setting) be detected,the system can automatically switch from a directional jamming mode toan omnidirectional jamming mode of operation. Such a mode of operationcan be determined in a scenario in which large salvo attacks areexpected (or detected).

In example implementations, the system 103 can also be operable toaccount for the proximity of friendly systems. For example, the systemcan be operable to receive an input from the user that sets the systemto either cease operation, or to switch to a specified mode ofoperation, when Blue Force Tracker (BFT), Identification Friend or Foe(IFF), or a similar system indicates that a friendly aircraft orcritically-deemed system that is dependent on SATNAV is within range ofthe jamming signal of the system 103, such as another incomingprojectile defense device dependant on SATNAV signals. Additionally, thesystem 103 can be operable to allow a user to set the system 103 to notoperate when certain specified systems or aircraft are nearby. This modecan be useful at facilities that cannot afford SATNAV disruption, have alow-risk of PGM attack, or areas located near a system where criticaloperations requiring SATNAV are taking place, such as attacks on enemyforces with PGMs. This mode can also be useful for VIP protection.

Based on date information inputs, like radar tracking, exampleimplementations of the system 103 can be operable to determine thelikely points of impact of a detected object. The system 103 can allow auser to specify that if the incoming object's determined impact areafalls within a user specified area, the system 103 can be operable toactivate a jamming option, including omnidirectional, directional, ordirectional to omnidirectional, or another option such as jamming at aparticular point in an object's flight path, customized to therequirements of the user. The system 103 can also be operable toprioritize the protection of one or more predicted impact locations overothers in the event that omnidirectional jamming mode is determined notto be feasible. For example, a user can use a numerical ranking system(e.g., from 1 to 10), indicating which target is the most important(e.g., assign the most critical target that should be defended apriority of “1”). The system can further be operable to respond toattacks originating from specified directions, or to switch modes basedon the number and direction of the detected attack. This addedflexibility can allow the example implementations of the invention to beresponsive in a variety of dynamic battlefield situations.

In example implementations, the system can also be operable tocommunicate operations information to other friendly devices. FIG. 2output 210 details system data from the system 103 to communicate itspresence and the activity of its jamming antennae to other friendlyunits through BFT or some other analogous system, and/or it cantransmit/broadcast a warning to alert friendly civilian equipment. Inaddition, a user can allow the system to broadcast its current operatingmode, for example directional or omnidirectional, via BFT, or radio, orsome other communication system and/or to announce when it is jammingand also the type of jamming it is conducting. In some exampleimplementations, a digital warning that a SATNAV jamming event isoccurring can be incorporated into the jamming signals themselves toprompt an automatic response from nearby UAVs or other automated systemsthat depend on the SATNAV signal, including civilian systems. In otherexample implementations, if the user enables the SATNAV disruptionwarning option, the system 103 can alert other units/aircraft orcivilian receivers that a jammer is in the area before any jammingoccurs.

In example implementations, the system 103 can also be operable to allowa user to specify times and dates that the system 103 will not operate,or within which it will enter a specified mode of operation. In exampleimplementations, a sensor next to the antennae records certain climacticconditions (e.g., wind speed), and is operable to send those sensorreadings to the system 103. If the user believes that certain climacticconditions, for example high winds, would potentially maketightly-targeted directional jamming inaccurate, the user could specifythat only omnidirectional jamming, or directional jamming with a widerbeam, are to be used in those climactic conditions. If the climacticconditions are present based on the sensor readings, then the system 103can be operative to go into the mode specified by the user for thoseconditions.

In some example implementations, the system can also be operable toallow a user to temporarily deactivate the system 103, or change itsoperating mode while critical operations that require SATNAV are takingplace. This setting can be scheduled in advance or activated by BFT,IFF, or a similar system.

In some example implementations, the system 103 can also be operable toreceive input from field detection systems, such as a battlefield radar,and only automatically activate when an attack is detected in which theincoming object is of a pre-selected type, such as a mortar, UAV, cruisemissile, rocket, or any combination of the preceding, and to ignore allnon-selected projectile types. Based on field detection systems, thesystem 103 can also be operable to only activate, for example, whenobjects known to have a potential SATNAV guidance are detected.

Referring again to FIG. 1, in example implementations, the system 103can also integrate a battlefield targeting radar 101 in the same housingto provide data input 201 to the decision-making software module 204.This can be useful in the event of deployment in a location that lackscounter-battery radar capabilities. In other example implementations,the radar can also be an existing system and integrated with the system103, rather than a separate system connecting to the system 103.

Referring again to FIG. 2, decision making software 204 can be one ormore microcontrollers operable to communicate with the system computer.The system computer can also have one or more microcontrollers, forexample processors, operable to execute the decision making software. Anexample implementation of this is illustrated in FIG. 3.

FIG. 3 is a block diagram of an example implementation showing examplecomponents of the system and some of the example various inputs/outputsto the system. Referring now to FIG. 3, system components and systeminputs/outputs of a an example implementation can include a systemcomputer containing decision-making software 301 that can be similar tothe software described in conjunction with element 204. The systemcomputer 301 can receive data input from a battlefield radar 302, auser, an IFF or BTF 303, or from a targeting radar 304. The input fromthe battlefield radar 302 can be similar to the on described for digitalsignal 201. The input from the user, IFF, BFT, or other systems 303 canbe similar to the one described for element 205 or 206. The data fromthe targeting radar 304 can be similar to that described for element202. The system computer 301 can also provide output data feedback tothe targeting radar 306, which can include, for example, the grosssearch area for the targeting radar. The system computer 301 can alsoprovide output data feedback to BFT, IFF, or other systems 308. Thisfeedback can be similar to the feedback illustrated in 210. The systemcomputer 301 can also provide a warning 307 to other systems when theSATNAV jammer is operating. The system 103 can provide orders 305 tomicrocontrollers 309 which transmit output control data 313 to a jammingantenna 312, and output control data 310 to an actuator 311 that orientsthe jamming antenna 312. When it receives an order, the jamming antennacan transmit or emit a SATNAV jamming signal 314 and a warning signal315 that the SATNAV jammer is operating. The warning signal 315 can bedigitally transmitted within the jamming signal 314 or separate from thejamming signal. The system can also transmit output control data tojammers 317 or actuators 318 as for control of additional antennae 316.

As can be seen in FIG. 3, example implementations can utilizemicrocontrollers to control the actuators that direct the movement ofthe directional emitters and control the SATNAV jammers. FIG. 3 detailsthe microcontrollers as separate from the microcontroller that executesthe decision making software residing within the system's computer.However, in other example implementations, these microcontrollers mightbe singular with multi-functions. In yet other example implementations,the system can include a plurality of microcontrollers.

An example implementation can include a SATNAV jammer or jammers 105that can transmit or emit signals to disrupt the acquisition ofsatellite signals used by incoming satellite guided threats. In exampleimplementations, based on user input, the system's automatic jammingresponse to an attack is emitted by a SATNAV jammer 105. The jammingsignals can be across all known SATNAV frequencies, or target particularfrequencies. The characteristics, including direction, of the jamming105 can be omnidirectional, directional wherein the arc can be specifiedby user or changed depending on the number and direction of targetedobjects, specifically targeted, or of a certain frequency or frequenciesall selected by a user. In example implementations, different objects102 can be targeted with different responses—for example, a targetedjamming response when an object that behaves like a mortar and anomnidirectional jamming response when an object is detected that behaveslike a rocket; or, for example, transmitting a targeted beam that jamscivilian GPS signals combined with omnidirectional GLONASS jammingwhenever an indirect fire attack is detected or a jamming responseagainst only military SATNAV signals when a glide-bomb attack isdetected. The user can also specify the signal strength of jammingagainst different signals that are transmitted simultaneously.

Example implementations can include a SATNAV jammer with, for example,one or more antennas, antenna arrays, and/or parabolic emitters, 207,208, or 312. The antennas and parabolic emitters can be directional oromnidirectional. Such antennae are known to those of ordinary skill inthe art. For example, a type of transmitting antenna this system 103 canuse would be a non-traversing directional antennae located at the top ofa tower. The antenna can be angled upward to automatically cover a largearea while attempting to leave ground equipment unaffected by thejamming signal. Field testing can determine the antenna type, properfrequency, power, width, or angle of the various jamming signals theuser can specify in order to respond to different adversaries indifferent environments. Based on sufficient data retrieved fromdetection systems, a user can create customized modes to respond indifferent ways to particular types of attack. For example, if theattacker only has mortars guided by a civilian GPS receiver, the usercan specify jamming only the civilian GPS signals when an incomingmortar attack is detected and no jamming response when a rocket attackis detected. Or, for example, if the user believes the potential enemyonly has SATNAV PGMs which can correct effectively above or below acertain altitude, the user can specify a jamming response only when adetected object is within these altitude parameters. As another example,the user can designate a particular response based upon a specified timeperiod.

One variety of antennae which the system 103 can include (or beoperative to communicate with) is a directional parabolic antenna withan actuator (or actuators) capable of rotating the directional antenna360 degrees and elevating it 200 or more degrees, for example. Thisantenna can include a tower or similar stand with directional jammingantennae at the top. To ensure the accuracy of firing solutions, somemodel antennae used could have a leveling actuator to ensure thedirectional antennae apparatus is level and carry out the jammingsolutions accurately. A microcontroller could also be attached to thedirectional jamming antennae to control actuators in response to thesystem's central computer.

Example implementations can include a multi-Global Navigation SatelliteSystem (GNSS) receiver that can be located directly under the jammer toprovide a close approximation of the jammer to the system's centralcomputer or any other computers or systems that are integrated with thesystem. This information could assist in calculating firing solutionsfor the directional antennae. Other measurement information can be usedto locate and calibrate the directional antennae. The multi-GNSSreceiver could also be used to confirm that some jamming signals areworking correctly.

Referring to FIG. 2, example implementations can include SATNAV jammeroutputs 207 and 209 that transmit or emit signals that spoof a PGM'snavigation computer to direct the PGM off its set-course to apredetermined location. Such “spoofing” can be completed by sendingfalse signals imitating SATNAV signals which would cause the PGM toguide itself to a pre-determined location.

In example implementations the system 103 can be integrated with, forexample, a military base automatic alarm system that sounds when aninbound attack is detected, for example via a “giant voice” system, orsome other audible alert system. In some implementations, the system canbe operable to, upon detection of an indirect fire attack, automaticallysound an audible signal alongside the alarm in order to reassurepersonnel and inform them that incoming SATNAV guided munitions arebeing jammed. This feature can serve to counter the psychologicaleffects of a possible PGM attack.

Example implementations of the system 103 can also include hardenedjamming antennae and/or placing the antennae at a distance from thesystem's components. The antennae can alternate their use during anattack to frustrate jam-homing munitions, and/or automatically switch toanother back-up antenna if one is disabled. Additionally, the system 103can automatically direct several directional antennae that are trackinga target or targets and emit identical SATNAV jamming signals to switchon and off while still ensuring that the targeted object or objects arepersistently illuminated.

In example implementations, the system 103 can work on any navigationsystem that uses a technology similar to SATNAV to enable navigation,such as ground based navigation systems.

What is claimed is:
 1. An electronic warfare defense system operablefor: receiving information from an incoming object detector, wherein theinformation comprises data regarding an incoming object; processing theinformation received from the incoming object detector; and sending acommand for an antenna to emit a jamming signal capable of disrupting aSATNAV broadcast signal potentially received by the incoming object. 2.The defense system of claim 1, wherein the incoming object detectorcomprises a battlefield radar.
 3. The defense system of claim 1, whereinthe jamming signal comprises a directional signal.
 4. The defense systemof claim 1, wherein the jamming signal comprises an omnidirectionalsignal.
 5. The defense system of claim 1, wherein the antenna comprisesa parabolic antenna.
 6. The defense system of claim 1, wherein thedefense system is operable for receiving user inputs, where in theinputs are used by the system to determine one or more modes ofoperation related to the emission of the jamming signal.
 7. The defensesystem of claim 1, wherein the jamming signal's characteristics areselected based upon the user inputs.
 8. The defense system of claim 1,wherein the jamming signal's frequency is selected based upon theinformation received from the incoming object detector.
 9. The defensesystem of claim 1, wherein the defense system is operable for receivinginformation from an identification system, and determining one or moremodes of operation related to the emission of the jamming signal basedon the information received from the identification system.
 10. Thedefense system of claim 1, wherein the defense system is operable fordetermining a mode of operation related to the emission of the jammingsignal based on information it uses indicating the presence of friendlySATNAV-dependent devices.
 11. The defense system of claim 1, wherein thesystem is operable for transmitting and/or emitting a warning signal tocomprising a warning that nearby friendly systems that a SATNAV jammeris active, and the type of jamming that may be conducted.
 12. Thedefense system of claim 1, wherein said incoming objects comprise one ormore of a PGM, missile, rocket, vehicle, unmanned vehicle, water-basedvehicle, and a torpedo.
 13. The defense system of claim 1, wherein thejamming signal is directed at the predicted location of an incomingobject.
 14. The defense system of claim 1, wherein the jamming signal isdirected at the actual location of an incoming object.
 15. The defensesystem of claim 1, wherein the antenna is physically controlled byactuators receiving a control signal from the defense system.
 16. Thedefense system of claim 1, wherein an alert is generated when thedefense system has made a decision as to what type of response isrequired.
 17. The defense system of claim 1, wherein the antennaalternates its jamming signal output to frustrate jam-homing attacks.18. The defense system of claim 1, wherein a backup antenna is selectedwhen the primary antenna is inoperable.
 19. The defense system of claim1, wherein the jamming signal comprises a spoofing signal.